Skin is the largest and one of the most complex body organs. It comprises from about 15 to 20% of the entire body weight and serves as a protective barrier to environmental toxins and assaults. Skin that is in good health is referred to as normalized. The skin's immune response to environmental conditions such as excessive sun exposure, cold weather, wind, or cigarette smoke can cause skin to become irritated or inflamed—in other words the skin is no longer normalized. For years cosmetics manufacturers have sold products for normalizing skin that included ingredients believed to have anti-inflammatory or anti-irritant properties. However, since there are a myriad of biological reactive pathways that contribute to skin inflammation and these products often contained ingredients that did not have any impact on any of these reactive pathways, they were not often as effective as they could have been. In other words, to effectively treat irritated or inflamed skin it is important to understand the biological pathways that contribute to the situation to begin with. Then active ingredients that exert a positive effect on blocking inflammatory pathways or stimulating pathways that promote resolution of the inflammatory state can be formulated into topical products.
Inflammation is a defense mechanism in organisms. There are 3 distinct phases of inflammation: the initiation phase, the amplification phase, and a resolution phase. The inflammatory process generates oxidized polyunsaturated fatty acids (PUFA) which have a role in stimulating the release of lipid mediators that assist in resolution of the inflammation, also referred to as pro-resolution lipid mediators. Examples of such pro-resolution lipid mediators include Resolvins, Maresins, Lipoxins, and Protectins.
In order to assess the efficacy of an active ingredient in resolving inflammation, accurate measurement of the various lipid mediators that are markers for the inflammatory state is necessary. To create products that contain active ingredients that exert a positive effect on the pro-resolution pathways to reduce the incidence and duration of inflammation is a very desirable commercial goal. However, one challenge is that measuring the effectiveness of an active ingredient on human test subjects challenged with inflammatory stimuli and observed for response is not always scientifically accurate since each individual differs in terms of sensitivity and immune response to challenge. It has been found that measuring certain PUFA markers will indicate the presence and concentration of various lipid mediators known to be involved in resolution of inflammation. It is one way to screen and identify actives that, when applied to skin, are capable of stimulating the release of skin's natural pro-resolution lipid mediators such as Resolvins, Maresins, Protectins, or Lipoxins, to reduce the incidence, duration, and severity of the inflammatory response.
It is an object of the invention to identify active ingredients that are effective in treating individuals with inflamed skin in need of normalization by stimulating the skin's natural pro-resolution lipid pathway.
It is a further object of the invention to provide a method and compositions for normalizing inflamed skin in an individual by topically applying actives that stimulate the skin's pro-resolution pathways and cause the skin to secrete pro-resolution lipid mediators in an amount sufficient to improve the condition of the skin.